Brass Knuckles Battery 4 Color Display 30ct 900MAH | SQUARE DISTRIBUTOR & WHOLESALER OF BRASS IN THE USA

Features:

2 Click Preheat Mode
Capacity: 900mAh
Customized: Customized
Logo Printing: with Logo Printing
Charging Type: Cable
Certification: FCC, RoHS, CE
Capacity: 900mAh
Variable Voltage: 3.2-4.1V
Voltage: Adjustable
Battery: 900mah
Color: Rainbow , Silver , Rose Pink , Gold , Brown wood

The battery's capacity, which is expressed in milliampere-hours (mAh), is most likely what the "900MAH" stands for. You can use the vape pen for a longer period of time before having to recharge it if the battery life is indicated by a larger mAh rating.

Batteries for vape pens under the Brass Knuckles brand are frequently used to heat THC oil cartridges. It's possible that the "30ct" you indicated referred to a pack of 30 Brass Knuckles batteries, but without more information, it's difficult to be certain.